register a global hotkey in Cococa

globalhotkey.m

#import <Carbon/Carbon.h>

@interface LXAppDelegate()
{
    EventHotKeyRef global_hotkey_ref;
}
- (void)hotKeyAction;
@end


static pascal OSStatus HotKeyEventHandlerProc(EventHandlerCallRef nextHandler,EventRef theEvent, void *userData)
{
    EventHotKeyID			hotKeyID;
    OSStatus				err			= eventNotHandledErr;
	UInt32					eventClass	= GetEventClass( theEvent );
	UInt32					eventKind	= GetEventKind( theEvent );
	
    switch ( eventClass )
	{
		case kEventClassKeyboard:
            if ( eventKind == kEventHotKeyReleased ){
                GetEventParameter( theEvent, kEventParamDirectObject, typeEventHotKeyID, NULL, sizeof(EventHotKeyID), NULL, &hotKeyID );
				if ( hotKeyID.signature == 'myglobalkey' ){
                    switch ( hotKeyID.id ){
						case 1:{
                            LXAppDelegate *appdelegate =  (__bridge LXAppDelegate *)userData;
                            [appdelegate hotKeyAction];
                        }
                         break;
					}
                }
            }
            break;
    }
    
    return err;
}

@implementation LXAppDelegate

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
    // Insert code here to initialize your application
    EventTypeSpec eventType;
    eventType.eventClass = kEventClassKeyboard;
    eventType.eventKind = kEventHotKeyReleased;
    InstallApplicationEventHandler(NewEventHandlerUPP(HotKeyEventHandlerProc), 1, &eventType, (__bridge void*)self, NULL);
    EventHotKeyID keyID = { 'myglobalkey', 1 };
    RegisterEventHotKey(kVK_ANSI_K, cmdKey, keyID, GetApplicationEventTarget(), 0, &global_hotkey_ref);
}

- (void)hotKeyAction
{
    NSLog(@"cmd+k hotKeyAction");
}

@end